This is a Continuation of Application Ser. No. 516,710, filed July 25, 1983, abandoned.
This invention relates to stereoscopic display systems, and more particularly, stereoscopic displays in which the images are provided by CRT displays. While the invention is described in particular detail with respect to arcade video games or conventional home entertainment devices, those skilled in the art will recognize the wider applicability of the inventive principles disclosed hereinafter. In particular, the invention has application wherever a three dimensional display is useful or desirable.
The prior art reveals many devices for displaying stereoscopic imagery in a fashion acceptable to general viewing audiences. While these prior art devices worked for their intended purposes, they suffer from a variety of drawbacks which severely limit their market potential. In general, the three-dimensional effect of prior art designs is produced by requiring the observer to position his head properly with respect to certain viewing ports; wearing filtering or light modulating glasses; or wearing a helmet, or similar headgear having the display mounted to it. The discomfort and inconvenience imposed upon an observer using these various prior art devices, especially when compared with the viewing ease offered by standard TV (CRT) displays, has contributed to the lack of wide acceptance of these systems.
Previous stereoscopic display systems also have suffered from poor image quality when compared to standard TV displays. For example, some devices have used color separation techniques to display a red image and a green image to the respective left and right eyes of an observer. Such a system design produces an unnatural color image presentation. Other systems use light polarization techniques to display stereo imagery. In this latter system design form, movement of the observer's head causes the polarized filters, especially those that are worn as glasses, to become ineffective and a confusing double image is displayed.
In yet another technique, a set of light modulating filters is placed in front of both eyes of an observer. The two light modulating filters are alternately changed from transparent to opaque in unison with the display, generally a single cathode ray tube (CRT), adapted to provide the corresponding left and right images required for stereo display. This method and its implementation causes a noticeable flicker effect.
Still other devices lack sufficient resolution because they use only half of the standard NTSC video bandwidth for each of two separate display channels.
The display system disclosed hereinafter overcomes these prior art deficiencies by providing a stereographic video display that requires no head mounted viewing aids. The system permits freedom of movement for a viewer or observer within an extended viewing envelope. Full color stereoscopic video display is provided to both eyes without the need for polarizing glasses. The design includes a tracking system that locates a viewer in three-dimensional space with relation to the display system. Viewer location is utilized to control the perspective of the projected scene presented to the observer. The system is particularly well adapted for providing stereoscopic displays in arcade game environments, although an embodiment for conventional home TV presentation in a stereoscopic system is also disclosed. As indicated above, other applications will occur to those skilled in the art. In particular, certain displays used for medical diagnosis are well suited for my invention.
One of the objects of this invention is to provide a display device which provides a stereoscopic display to an observer.
Another object of this invention is to provide a stereoscopic display that does not require the use of head mounted viewing aids.
Another object of this invention is to provide a stereoscopic display that exhibits resolution comparable to standard NTSC broadcast video displays.
Another object of this invention is to provide a relatively low cost stereoscopic display system.
Another object of this invention is to provide a display system in which head movement of the observer is tracked and utilized to adjust the image presented to the observer.
Other objects of this invention will be apparent to those skilled in the art in light of the following description and accompanying drawings.